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1.
J Cardiovasc Electrophysiol ; 35(3): 608-617, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37877234

RESUMO

Coronavirus disease 2019 (COVID-19) has led to a worldwide pandemic that continues to transform but will not go away. Cardiovascular dysautonomia in postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection has led to persistent symptoms in a large number of patients. Here, we define the condition and its associated symptoms as well as potential mechanisms responsible. We provide a careful and complete overview of the topic addressing novel studies and a generalized approach to the management of individuals with this complex and potentially debilitating problem. We also discuss future research directions and the important knowledge gaps to be addressed in ongoing and planned studies.


Assuntos
Doenças do Sistema Nervoso Autônomo , COVID-19 , Humanos , COVID-19/complicações , SARS-CoV-2 , Progressão da Doença , Pandemias
2.
Clin Sci (Lond) ; 138(15): 975-985, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39037711

RESUMO

The mechanisms underlying endothelial dysfunction in Type 1 and Type 2 diabetes (T1DM and T2DM) are unresolved. The red blood cells (RBCs) with increased arginase activity induce endothelial dysfunction in T2DM, but the implications of RBCs and the role of arginase inhibition in T1DM are unexplored. We aimed to investigate the differences in endothelial function in patients with T1DM and T2DM, with focus on RBCs and arginase. Thirteen patients with T1DM and twenty-six patients with T2DM, matched for HbA1c and sex were included. In vivo endothelium-dependent and -independent vasodilation (EDV and EIDV) were assessed by venous occlusion plethysmography before and after administration of an arginase inhibitor. RBCs were co-incubated with rat aortic segments for 18h followed by evaluation of endothelium-dependent (EDR) and -independent relaxation (EIDR) in isolated organ chambers. In vivo EDV, but not EIDV, was significantly impaired in patients with T2DM compared with patients with T1DM. Arginase inhibition resulted in improved EDV only in T2DM. RBCs from patients with T2DM induced impaired EDR but not EIDR in isolated aortic segments, whereas RBCs from patients with T1DM did not affect EDR nor EIDR. The present study demonstrates markedly impaired EDV in patients with T2DM in comparison with T1DM. In addition, it highlights the divergent roles of RBCs and arginase in mediating endothelial dysfunction in T1DM and T2DM. While endothelial dysfunction is mediated via RBCs and arginase in T2DM, these phenomena are not prominent in T1DM thereby indicating distinct differences in underlying mechanisms.


Assuntos
Arginase , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Endotélio Vascular , Eritrócitos , Vasodilatação , Humanos , Arginase/metabolismo , Arginase/antagonistas & inibidores , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/sangue , Masculino , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Feminino , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/sangue , Pessoa de Meia-Idade , Endotélio Vascular/fisiopatologia , Animais , Adulto , Idoso , Aorta/fisiopatologia , Inibidores Enzimáticos/farmacologia
3.
Clin Gastroenterol Hepatol ; 21(13): 3356-3364.e9, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37245713

RESUMO

BACKGROUND AND AIMS: Inflammatory diseases are associated with an increased risk of incident major adverse cardiovascular events (MACE). However, data on MACE are lacking in large population-based histopathology cohorts of microscopic colitis (MC). METHODS: This study included all Swedish adults with MC without previous cardiovascular disease (1990-2017; N = 11,018). MC and subtypes (collagenous colitis and lymphocytic colitis) were defined from prospectively recorded intestinal histopathology reports from all pathology departments (n = 28) in Sweden. MC patients were matched for age, sex, calendar year, and county with up to 5 reference individuals (N = 48,371) without MC or cardiovascular disease. Sensitivity analyses included full sibling comparisons, and adjustment for cardiovascular medication and healthcare utilization. Multivariable-adjusted hazard ratios for MACE (any of ischemic heart disease, congestive heart failure, stroke, and cardiovascular mortality) were calculated using Cox proportional hazards modelling. RESULTS: Over a median of 6.6 years of follow-up, 2181 (19.8%) incident cases of MACE were confirmed in MC patients and 6661 (13.8%) in reference individuals. MC patients had a higher overall risk of MACE outcomes compared with reference individuals (adjusted hazard ratio [aHR], 1.27; 95% confidence interval [CI], 1.21-1.33) and higher risk of its components: ischemic heart disease (aHR, 1.38; 95% CI, 1.28-1.48), congestive heart failure (aHR, 1.32; 95% CI, 1.22-1.43), and stroke (aHR, 1.12; 95% CI, 1.02-1.23) but not cardiovascular mortality (aHR, 1.07; 95% CI, 0.98-1.18). The results remained robust in the sensitivity analyses. CONCLUSIONS: Compared with reference individuals, MC patients had a 27% higher risk of incident MACE, equal to 1 extra case of MACE for every 13 MC patients followed for 10 years.


Assuntos
Doenças Cardiovasculares , Colite Microscópica , Insuficiência Cardíaca , Isquemia Miocárdica , Acidente Vascular Cerebral , Adulto , Humanos , Estudos de Coortes , Doenças Cardiovasculares/epidemiologia , Insuficiência Cardíaca/epidemiologia , Colite Microscópica/epidemiologia , Colite Microscópica/patologia , Fatores de Risco
4.
J Intern Med ; 293(2): 228-245, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36324273

RESUMO

BACKGROUND: Patients with familial hypercholesterolemia (FH) display high levels of low-density lipoprotein cholesterol (LDL-c), endothelial dysfunction, and increased risk of premature atherosclerosis. We have previously shown that red blood cells (RBCs) from patients with type 2 diabetes induce endothelial dysfunction through increased arginase 1 and reactive oxygen species (ROS). OBJECTIVE: To test the hypothesis that RBCs from patients with FH (FH-RBCs) and elevated LDL-c induce endothelial dysfunction. METHODS AND RESULTS: FH-RBCs and LDL-c >5.0 mM induced endothelial dysfunction following 18-h incubation with isolated aortic rings from healthy rats compared to FH-RBCs and LDL-c <2.5 mM or RBCs from healthy subjects (H-RBCs). Inhibition of vascular but not RBC arginase attenuated the degree of endothelial dysfunction induced by FH-RBCs and LDL-c >5.0 mM. Furthermore, arginase 1 but not arginase 2 was elevated in the vasculature of aortic segments after incubation with FH-RBCs and LDL-c >5.0 mM. A superoxide scavenger, present throughout the 18-h incubation, attenuated the degree of endothelial dysfunction induced by FH-RBCs and LDL-c >5.0 mM. ROS production was elevated in these RBCs in comparison with H-RBCs. Scavenging of vascular ROS through various antioxidants also attenuated the degree of endothelial dysfunction induced by FH-RBCs and LDL-c >5.0 mM. This was corroborated by an increase in the lipid peroxidation product 4-hydroxynonenal. Lipidomic analysis of RBC lysates did not reveal any significant changes across the groups. CONCLUSION: FH-RBCs induce endothelial dysfunction dependent on LDL-c levels via arginase 1 and ROS-dependent mechanisms.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperlipoproteinemia Tipo II , Animais , Ratos , LDL-Colesterol , Espécies Reativas de Oxigênio/metabolismo , Hiperlipoproteinemia Tipo II/complicações , Eritrócitos/metabolismo
5.
Am J Physiol Heart Circ Physiol ; 323(5): H1004-H1009, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206054

RESUMO

Remote ischemic conditioning (RIC), brief repetitive cycles of ischemia and reperfusion in remote tissues, is known to induce robust protection against myocardial ischemia-reperfusion (I/R) injury in preclinical studies. However, translation of the beneficial effects to the clinical setting has been challenging. A possibility is that comorbidities, including hypercholesterolemia, interfere with the protective mechanisms of RIC. The aim of this study was to test if hypercholesterolemia attenuates the efficacy of RIC in patients with hypercholesterolemia. Patients with familial hypercholesterolemia (FH) with high (≥5.5 mmol/L) low-density lipoprotein cholesterol (LDL-C), FH with low (≤2.5 mmol/L) and healthy control subjects (n = 12 in each group) were included. Flow-mediated vasodilatation (FMD) of the brachial artery was evaluated, before and after a 20-min period of forearm ischemia and 20 min reperfusion (I/R) as a measure of endothelial function. Study subjects were randomized to a RIC protocol consisting of four cycles of 5 min of leg ischemia or sham using a crossover design. Forearm I/R induced significant reduction in FMD in all three groups during the sham procedure. RIC protected from endothelial dysfunction induced by forearm ischemia-reperfusion in healthy controls [FMD baseline 2.8 ± 2.3 vs. FMD after I/R + RIC 4.5 ± 4.0%; means (SD)] and in patients with FH with low LDL-C (4.5 ± 3.5 vs. 4.4 ± 4.2%). By contrast, RIC fails to protect against I/R-induced endothelial dysfunction in patients with FH and high LDL-C (3.9 ± 3.0 vs. 1.1 ± 1.5%; P < 0.01). These findings provide the first evidence in humans that the protective effect of RIC is lost in patients with elevated cholesterol.NEW & NOTEWORTHY We investigated the impact of hypercholesterolemia on the protective effect of RIC on ischemia-reperfusion injury in a well-characterized patient population with isolated hypercholesterolemia. The results show that the protective effect of RIC is absent in patients with hypercholesterolemia but is apparent in patients with hypercholesterolemic following treatment with lipid-lowering drugs. The results are of importance for the understanding of how comorbidities affect the therapeutic potential of RIC.


Assuntos
Hipercolesterolemia , Traumatismo por Reperfusão Miocárdica , Humanos , LDL-Colesterol , Hipercolesterolemia/complicações , Hipercolesterolemia/diagnóstico , Isquemia , Traumatismo por Reperfusão Miocárdica/prevenção & controle
6.
Basic Res Cardiol ; 117(1): 46, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36112326

RESUMO

Red blood cells (RBCs) are suggested to play a role in cardiovascular regulation by exporting nitric oxide (NO) bioactivity and ATP under hypoxia. It remains unknown whether such beneficial effects of RBCs are protective in patients with acute myocardial infarction. We investigated whether RBCs from patients with ST-elevation myocardial infarction (STEMI) protect against myocardial ischemia-reperfusion injury and whether such effect involves NO and purinergic signaling in the RBCs. RBCs from patients with STEMI undergoing primary coronary intervention and healthy controls were administered to isolated rat hearts subjected to global ischemia and reperfusion. Compared to RBCs from healthy controls, RBCs from STEMI patients reduced myocardial infarct size (30 ± 12% RBC healthy vs. 11 ± 5% RBC STEMI patients, P < 0.001), improved recovery of left-ventricular developed pressure and dP/dt and reduced left-ventricular end-diastolic pressure in hearts subjected to ischemia-reperfusion. Inhibition of RBC NO synthase with L-NAME or soluble guanylyl cyclase (sGC) with ODQ, and inhibition of cardiac protein kinase G (PKG) abolished the cardioprotective effect. Furthermore, the non-selective purinergic P2 receptor antagonist PPADS but not the P1 receptor antagonist 8PT attenuated the cardioprotection induced by RBCs from STEMI patients. The P2Y13 receptor was expressed in RBCs and the cardioprotection was abolished by the P2Y13 receptor antagonist MRS2211. By contrast, perfusion with PPADS, L-NAME, or ODQ prior to RBCs administration failed to block the cardioprotection induced by RBCs from STEMI patients. Administration of RBCs from healthy subjects following pre-incubation with an ATP analog reduced infarct size from 20 ± 6 to 7 ± 2% (P < 0.001), and this effect was abolished by ODQ and MRS2211. This study demonstrates a novel function of RBCs in STEMI patients providing protection against myocardial ischemia-reperfusion injury through the P2Y13 receptor and the NO-sGC-PKG pathway.


Assuntos
Eritrócitos , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Infarto do Miocárdio com Supradesnível do Segmento ST , Trifosfato de Adenosina , Animais , Proteínas Quinases Dependentes de GMP Cíclico , Eritrócitos/metabolismo , Humanos , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/terapia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase , Antagonistas do Receptor Purinérgico P2 , Ratos , Receptores Purinérgicos P2/metabolismo , Infarto do Miocárdio com Supradesnível do Segmento ST/metabolismo , Guanilil Ciclase Solúvel
7.
J Microsc ; 286(3): 245-251, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35348197

RESUMO

The process of examining and analysing insulating materials using a scanning electron microscope usually accompanied by an important phenomenon called the mirror effect or charging effects. Such effects arise due to the ability of insulators to trapping charges at the sample surface for a period. The accumulation of charges leads to creating an electric potential that may be strong enough to deflect incident electrons in the same way a convex mirror scatters light. The created potential depends mainly on the charge amount, charges accumulation profile and the way by which the charges arranging themselves. Present work aims at exploring the influences of the charges distribution profile and their arrangements. In order to achieve such a goal, the sample-surface potential has theoretically formulated to include various shapes of the accumulated charges. Thereafter, the correspondence expression of the mirror plot curve is defined to link the geometrical distribution of charges. The resultant formula for the surface potential and mirror plot showed that the point charge approximation is a special case of the presented model. The formula of mirror-plot curve has put forward to be a detection tool for the actual build-up form that the electrons accumulating might take on the insulator surface. Simulation results have shown that the presented procedure could be adopted to search for the optimum distribution profile that may meet an experimental data. It is found that the most probable profile that accumulated electrons might form is the semi-hemispheric one. The surface of this profile is generally an ellipsoid of a variant axis rather a flat one. Results also reveal that, all the multipole-moment types could be formed for any shape of accumulation, but their weightiness progressively decreases whenever the pole-number increases. Furthermore, the configurations that trapped electrons arrange themselves within each distribution profile can be traced with the variation of scanning potential.


Assuntos
Eletricidade , Elétrons , Simulação por Computador
8.
Pharmacology ; 107(3-4): 160-166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34929688

RESUMO

INTRODUCTION: Sunitinib, a multi-targeted tyrosine kinase receptor inhibitor used to treat renal-cell carcinoma and gastrointestinal stromal tumor, was recently shown to have a beneficial effect on metabolism in type 2 diabetes (T2D). Endothelial dysfunction is a key factor behind macro- and microvascular complications in T2D. The effect of sunitinib on endothelial function in T2D remains, however, unclear. We therefore tested the hypothesis that sunitinib ameliorates endothelial dysfunction in T2D. METHODS: Sunitinib (2 mg/kg/day, by gavage) was administered to T2D Goto-Kakizaki (GK) rats for 6 weeks, while water was given to GK and Wistar rats as controls. Hemodynamic, inflammatory, and metabolic parameters as well as endothelial function were measured. RESULTS: Systolic, mean arterial blood pressures, plasma tumor necrosis factor α levels, kidney weight to body weight (BW) ratio, and glucose levels were higher, while BW was lower in GK rats than in Wistar rats. Six-week treatment with sunitinib in GK rats did not affect these parameters but suppressed the increase in glucose levels. Endothelium-dependent relaxations were reduced in both aortas and mesenteric arteries isolated from GK as compared to Wistar rats, which was markedly reversed in both types of arteries from GK rats treated with sunitinib. CONCLUSIONS: This study demonstrates that sunitinib has a glucose-lowering effect and ameliorates endothelial dysfunction in both conduit and resistance arteries of GK rats.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Endotélio Vascular , Ratos , Ratos Wistar , Sunitinibe/metabolismo , Sunitinibe/farmacologia , Sunitinibe/uso terapêutico
9.
Proc Natl Acad Sci U S A ; 116(52): 26332-26342, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31811026

RESUMO

Optogenetics, which uses visible light to control the cells genetically modified with light-gated ion channels, is a powerful tool for precise deconstruction of neural circuitry with neuron-subtype specificity. However, due to limited tissue penetration of visible light, invasive craniotomy and intracranial implantation of tethered optical fibers are usually required for in vivo optogenetic modulation. Here we report mechanoluminescent nanoparticles that can act as local light sources in the brain when triggered by brain-penetrant focused ultrasound (FUS) through intact scalp and skull. Mechanoluminescent nanoparticles can be delivered into the blood circulation via i.v. injection, recharged by 400-nm photoexcitation light in superficial blood vessels during circulation, and turned on by FUS to emit 470-nm light repetitively in the intact brain for optogenetic stimulation. Unlike the conventional "outside-in" approaches of optogenetics with fiber implantation, our method provides an "inside-out" approach to deliver nanoscopic light emitters via the intrinsic circulatory system and switch them on and off at any time and location of interest in the brain without extravasation through a minimally invasive ultrasound interface.

10.
CMAJ ; 193(31): E1203-E1212, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373268

RESUMO

BACKGROUND: The COVID-19 pandemic has exacerbated disparities in poverty and illness for people in vulnerable circumstances in ethnocultural communities. We sought to understand the evolving impacts of COVID-19 on ethnocultural communities to inform intersectoral advocacy and community action. METHODS: The Illuminate Project used participatory action research, with cultural health brokers as peer researchers, from Sept. 21 to Dec. 31, 2020, in Edmonton, Alberta. Twenty-one peer researchers collected narratives from members of ethnocultural communities and self-interpreted them as they entered the narratives into the SenseMaker platform, a mixed-method data collection tool. The entire research team analyzed real-time, aggregate, quantitative and qualitative data to identify emerging thematic domains, then visualized these domains with social network analysis. RESULTS: Brokers serving diverse communities collected 773 narratives. Identified domains illuminate the evolving and entangled impacts of COVID-19 including the following: COVID-19 prevention and management; care of acute, chronic and serious illnesses other than COVID-19; maternal care; mental health and triggers of past trauma; financial insecurity; impact on children and youth and seniors; and legal concerns. We identified that community social capital and cultural brokering are key assets that facilitate access to formal health and social system supports. INTERPRETATION: The Illuminate Project has illustrated the entangled, systemic issues that result in poor health among vulnerable members of ethnocultural communities, and the exacerbating effects of COVID-19, which also increased barriers to mitigation. Cultural brokering and community social capital are key supports for people during the COVID-19 pandemic. These findings can inform policy to reduce harm and support community resiliency.


Assuntos
COVID-19/etnologia , Serviços de Saúde Comunitária/organização & administração , Pandemias , Populações Vulneráveis/etnologia , Alberta/epidemiologia , COVID-19/prevenção & controle , COVID-19/terapia , Informação de Saúde ao Consumidor , Feminino , Estresse Financeiro , Pesquisa sobre Serviços de Saúde , Disparidades em Assistência à Saúde , Humanos , Masculino , Pobreza , SARS-CoV-2 , Capital Social , Análise de Rede Social , Apoio Social
11.
Trop Anim Health Prod ; 53(2): 192, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33660073

RESUMO

A cross-sectional study was carried out in the period between January and April 2019 with the aim of establishing prevalence of Newcastle disease (ND) in backyard chickens in Banadir region of Somalia using indirect enzyme-linked immunosorbent assay (iELISA). A total of 373 unvaccinated free scavenging backyard chickens were sampled from five districts in Banadir region, namely Dharkenley, Hodan, Wadajir, Hawlwadag, and Daynile. The overall prevalence was found to be 39.4% (95% confidence interval: 34.6-44.4%) with a mean antibody titre of 3844.10 ± 263.3 (standard error). The seroprevalence of ND virus (NDV) antibody in Wadajir district was the highest (66.6%) followed by Hawlwadag, Daynile, Dharkenley, and Hodan with prevalence of 56%, 42.1%, 42.35%, and 10.6%, respectively, with statistically significant differences (P < 0.05). Adult chickens had significantly higher prevalence (43.8%) than growers (19.4%) (P < 0.05). The present study, which is the first of its kind in Somalia to the best of our knowledge, concluded that the disease is highly prevalent in the study area; therefore, molecular studies on the characteristics of circulating strains are to be carried out in order to develop an evidence-based control programme and minimize the economic and social impacts of ND on smallholders.


Assuntos
Galinhas/virologia , Doença de Newcastle/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Animais , Anticorpos Antivirais/imunologia , Estudos Transversais , Feminino , Masculino , Vírus da Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/isolamento & purificação , Estudos Soroepidemiológicos , Somália/epidemiologia
12.
J Cell Physiol ; 234(5): 5655-5663, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30515806

RESUMO

It is now fully recognized that along with multiple physiological functions, angiogenesis is also involved in the fundamental process and pathobiology of several disorders including cancer. Recent studies have fully established the role of angiogenesis in cancer progression as well as invasion and metastasis. Consequently, many therapeutic agents such as monoclonal antibodies targeting angiogenesis pathway have been introduced in clinic with the hope for improving the outcomes of cancer therapy. Bevacizumab (Avastin®) was the first anti-vascular endothelial growth factor (VEGF) targeting monoclonal antibody developed with this purpose and soon received its accelerated US Food and Drug Administration (FDA) approval for treatment of patients with metastatic breast cancer in 2008. However, the failure to meet expecting results in different follow-up studies, forced FDA to remove bevacizumab approval for metastatic breast cancer. Investigations have now revealed that while suppressing VEGF pathway initially decreases tumor progression rate and vasculature density, activation of several interrelated pathways and signaling molecules following VEGF blockade compensate the insufficiency of VEGF and initially blocked angiogenesis, explaining in part the failure observed with bevacizumab single therapy. In present review, we introduce some of the main pathways and signaling molecules involved in angiogenesis and then propose how their interconnection may result in development of resistance to bevacizumab.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico , Neovascularização Patológica , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/efeitos adversos , Animais , Bevacizumab/efeitos adversos , Humanos , Neoplasias/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Transdução de Sinais , Hipóxia Tumoral , Microambiente Tumoral
13.
Int J Mol Sci ; 19(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544633

RESUMO

Purinergic signaling may be altered in diabetes accounting for endothelial dysfunction. Uridine adenosine tetraphosphate (Up4A), a novel dinucleotide substance, regulates vascular function via both purinergic P1 and P2 receptors (PR). Up4A enhances vascular contraction in isolated arteries of diabetic rats likely through P2R. However, the precise involvement of PRs in endothelial dysfunction and the vasoconstrictor response to Up4A in diabetes has not been fully elucidated. We tested whether inhibition of PRs improved endothelial function and attenuated Up4A-mediated vascular contraction using both aortas and mesenteric arteries of type 2 diabetic (T2D) Goto Kakizaki (GK) rats vs. control Wistar (WT) rats. Endothelium-dependent (EDR) but not endothelium-independent relaxation was significantly impaired in both aortas and mesenteric arteries from GK vs. WT rats. Non-selective inhibition of P1R or P2R significantly improved EDR in aortas but not mesenteric arteries from GK rats. Inhibition of A1R, P2X7R, or P2Y6R significantly improved EDR in aortas. Vasoconstrictor response to Up4A was enhanced in aortas but not mesenteric arteries of GK vs. WT rats via involvement of A1R and P2X7R but not P2Y6R. Depletion of major endothelial component nitric oxide enhanced Up4A-induced aortic contraction to a similar extent between WT and GK rats. No significant differences in protein levels of A1R, P2X7R, and P2Y6R in aortas from GK and WT rats were observed. These data suggest that altered PR sensitivity accounts for endothelial dysfunction in aortas in diabetes. Modulating PRs may represent a potential therapy for improving endothelial function.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Animais , Diabetes Mellitus Experimental , Fosfatos de Dinucleosídeos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Masculino , Ratos , Ratos Wistar , Receptores Purinérgicos/metabolismo , Vasoconstrição/efeitos dos fármacos
14.
J Pak Med Assoc ; 67(5): 745-751, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28507364

RESUMO

OBJECTIVE: To evaluate the effect of using peer role-playing in learning the communication skills as a step in the development of the communication skills training course delivered to pre-clinical medical students. METHODS: This study was conducted at the King Abdulaziz University, Jeddah, Saudi Arabia, between September 2014 and February 2015 and comprised medical students. Mixed methods design was used to evaluate the developed communication skills training course. Tests were conducted before and after the communication skills training course to assess the students' self-reported communication. After the course, the students completed a satisfaction survey. Focus groups were conducted to assess the behavioural and organisational changes induced by the course. SPSS 16 was used for data analysis.. RESULTS: Of the293 respondents, 246(84%) were satisfied with the course. Overall, 169(58%) subjects chose the lectures as the most helpful methods for learning the communication skills while 124(42%) considered practical sessions as the most helpful method. Besides, 237(81%) respondents reported that the role-play was beneficial for their learning, while 219(75%) perceived the video-taped role-play as an appropriate method for assessing the communication skills. CONCLUSIONS: Peer role-play was found to be a feasible and well-perceived alternative method in facilitating the acquisition of communication skills..


Assuntos
Competência Clínica , Comunicação , Currículo , Educação de Graduação em Medicina/métodos , Grupo Associado , Desempenho de Papéis , Feminino , Grupos Focais , Humanos , Masculino , Competência Profissional , Arábia Saudita , Estudantes de Medicina
15.
Br J Haematol ; 168(5): 639-45, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25521017

RESUMO

Superficial vein thrombosis (SVT) was considered to be a benign and self-limiting condition. However, it is now appreciated that a significant proportion of those presenting with SVT will have concomitant deep vein thrombosis or pulmonary embolism, or are at significant risk of developing deep venous thromboembolism. Potential therapeutic options include topical preparations, compression therapy (stockings, bandages), medication such as non-steroidal anti-inflammatory drugs (NSAIDs) or anticoagulants (therapeutic or prophylactic doses) and surgery, ligation or stripping, of superficial veins. The treatment of choice is therapeutic/intermediate dose low molecular weight heparin or prophylactic dose fondaparinux administered for 4-6 weeks. The cost-effectiveness of treatment is a concern and more targeted therapy is required.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Polissacarídeos/uso terapêutico , Trombose Venosa/tratamento farmacológico , Fondaparinux , Humanos , Fatores de Risco , Fatores de Tempo , Trombose Venosa/patologia
16.
Br J Haematol ; 169(6): 768-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25754016

RESUMO

Treatment of congenital haemophilia with factor VIII and IX concentrates often requires frequent infusions. This has obvious implications in establishing effective administration strategies and, in turn, adherence. To overcome these issues, three main technologies--polyethylene-glycol, Fc-neonatal IgG1 and albumin fusion products--have emerged into various stages of clinical development. Published data indicates an approximately 1·5- and fivefold increase in half-life of factor VIII and IX, respectively, compared to standard recombinant concentrates. Studies into efficacy and safety are starting to be published. Monitoring and optimal use of these new concentrates remains unknown. Weekly factor IX prophylaxis appears to be a feasible prophylactic regimen in haemophilia B patients. Weekly longer-acting FVIII is unlikely to provide adequate prophylaxis in most patients with haemophilia A but may reduce the frequency of infusions. Ongoing clinical trials and real life experience will help shape how these products can be used in practice and their cost effectiveness. The drive for convenience however should not overshadow the ultimate goal of prophylaxis, namely, preventing bleeding and arthropathy.


Assuntos
Fator IX/uso terapêutico , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemofilia B/tratamento farmacológico , Monitoramento de Medicamentos , Fator IX/administração & dosagem , Fator IX/farmacocinética , Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Meia-Vida , Humanos , Adesão à Medicação , Resultado do Tratamento
17.
Oral Oncol ; 156: 106939, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38991396

RESUMO

BACKGROUND: Papilloma DNA virus which is most common sexually transmitted disease to both sexes. The infection either benign or malignant affecting head and neck region. AIM OF THE STUDY: Assess the level of knowledge, and attitude, of medical students about Human Papilloma virus, vaccine, and its role in head and neck cancer development. MATERIALS AND METHODS: A descriptive cross-sectional survey was conducted on 357 undergraduate medical students. Data were collected by online Google form researcher made questionnaires which was analyzed using SPSS 25. RESULTS: There are 357 medical undergraduate students from different educational stages participated in this study. This study was shown 176 (49.3 %) of medical students agreed that smoking Tobacco are the most common causes for development oral cancer followed by viruses 98 (27.5 %), that 57.4 % of medical students reported that HPV was the main viral cause. As for the questions concerning HPV mode of transmission, almost (85.7 %) stated sexual transmission, (79.8 %) skin to skin direct contact. Most of the participants (92.2 %) agreed that primary prevention can decrease the risk of infection with HPV, and 43.4 % strongly agreed that vaccination plays an important role in HPV prevention. CONCLUSIONS: There is a requirement within the existing curriculum and syllabus to include more education, seminars, and training courses on HPV, role in HNC, prevention, and vaccination, and mainly for students in the preclinical academic years. Application of a virtual classroom viral module or communicating workshop would likely improve knowledge and attitudes of the students for their future medical tasks.


Assuntos
Neoplasias de Cabeça e Pescoço , Conhecimentos, Atitudes e Prática em Saúde , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Estudantes de Medicina , Humanos , Estudantes de Medicina/psicologia , Masculino , Feminino , Estudos Transversais , Neoplasias de Cabeça e Pescoço/virologia , Infecções por Papillomavirus/prevenção & controle , Adulto , Inquéritos e Questionários , Adulto Jovem , Papillomavirus Humano
18.
Atherosclerosis ; 389: 117439, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219650

RESUMO

BACKGROUND AND AIMS: Microvascular dysfunction underlies many cardiovascular disease conditions; little is known regarding its presence in individuals with high levels of lipoprotein(a) [Lp(a)]. The aim of the present study was to determine the frequency of microvascular dysfunction among such subjects with and without concomitant familial hypercholesterolemia (FH). METHODS: Four groups of asymptomatic individuals aged 30-59 years, without manifest cardiovascular disease, were recruited (n = 30 per group): controls with Lp(a) < 30 nmol/L, mutation-confirmed FH with Lp(a) < 30 nmol/L, or >125 nmol/L, and individuals with isolated Lp(a) > 125 nmol/L. Participants underwent evaluation of myocardial microvascular function by measuring coronary flow reserve (CFR) using transthoracic Doppler echocardiography, and of peripheral microvascular endothelial function by peripheral arterial tonometry. RESULTS: The groups were balanced in age, sex, and body mass index. Each of the three dyslipoproteinaemic groups had a greater proportion of individuals with impaired coronary flow reserve, 30%, compared to 6.7% of controls (p = 0.014). The median CFR levels did not differ significantly between the four groups, however. Cholesterol-lowering treatment time was longer in the individuals with normal than in those with impaired CFR in the FH + Lp(a) > 125 group (p = 0.023), but not in the group with FH + Lp(a) < 30 (p = 0.468). There was no difference in peripheral endothelial function between the groups. CONCLUSIONS: Coronary microvascular dysfunction is more prevalent in asymptomatic individuals with isolated Lp(a) elevation and in heterozygous FH both with and without high Lp(a) compared to healthy controls. Cholesterol-lowering treatment could potentially prevent the development of microvascular dysfunction.


Assuntos
Doenças Cardiovasculares , Hiperlipoproteinemia Tipo II , Isquemia Miocárdica , Humanos , Lipoproteína(a) , Doenças Cardiovasculares/complicações , Prevalência , Hiperlipoproteinemia Tipo II/complicações , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiologia , Colesterol
19.
ACS Omega ; 9(6): 7085-7107, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38371760

RESUMO

This investigation looks at the Late Triassic Baluti Formation's organic geochemical, mineralogical, and petrographical characteristics from a single exploration well (TT-22) near the Taq Taq oilfield in northern Iraq. The Baluti Formation shale samples that were studied in the studied well have high total organic carbon (TOC %) values up to 4.92 wt % and mostly hydrogen-rich types I and II kerogen with a minor gradient to types II/III and III kerogen, indicating a good oil-source rock. The hydrogen-rich kerogen was also confirmed by various organic matter (OM) origins and depositional environment-related biomarkers. The biomarker indicators demonstrate that the Baluti shale was deposited under anoxic conditions and contains a variety of OM generated mostly from algae marine and other aqueous organic materials, along with some terrigenous land plants. The geochemical and optical maturity indicators show that most of the examined Baluti shale samples, with a deep burial depth of more than 4000 m, are thermally mature, thus defining peak-mature to late-mature stages of the oil generation window. According to the basin models, from the late Miocene to the present, between 10 and 59% of the kerogen in the Baluti shale source rock has been transformed into oil, which is consistent with the VR values between 0.77 and 1.08%. The presence of the oil crossover in these shale rocks with an oil saturation index of more than 100 mg HC/g rock supports the maximal oil generation from the Baluti source rock system. Additionally, there was little oil expulsion from the Baluti source rock system at the end of the late Miocene, with transformation ratio values below 60% (59%). Considering the more significant oil generation and little expulsion, a high pressure was generated and forced the brittle minerals of the Baluti shales (mainly quartz), creating a natural fracture system as recognized and observed in the thin section. This natural fracture system enhances the porosity system of tight shale rocks of the Baluti Formation, giving rise to a high probability of oil production using hydraulic fracturing stimulation.

20.
Sci Rep ; 14(1): 19033, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152178

RESUMO

Organic rich sedimentary rocks of the Late Cretaceous Muwaqqar Formation from the Lajjun outcrop in the Lajjun Sub-basin, Western Central Jordan were geochemically analyzed. This study integrates kerogen microscopy of the isolated kerogen from 10 oil shale samples with a new finding from unconventional geochemical methods [i.e., ultimate elemental (CHNS), fourier transform infrared spectroscopy and pyrolysis-gas chromatography (Py-GC)] to decipher the molecular structure of the analyzed isolated kerogen fraction and evaluate the kerogen composition and characteristics. The optical kerogen microscopy shows that the isolated kerogen from the studied oil shales is originated from marine assemblages [i.e., algae, bituminite and fluorescence amorphous organic matter] with minor amounts of plant origin organic matter (i.e., spores). This finding suggests that the studied kerogen is hydrogen-rich kerogen, and has the potential to generate high paraffinic oil with low wax content. The dominance of such hydrogen-rich kerogen (mainly Type II) was confirmed from the multi-geochemical ratios, including high hydrogen/carbon atomic of more than 1.30 and high A-factor of more than 0.60. This claim agrees with the molecular structure of the kerogen derived from Py-GC results, which suggest that the studied kerogen is mainly Type II-S kerogen exhibiting the possibility of producing high sulphur oils during earlier stages of diagenesis, according to bulk kinetic modeling. The kinetic models of the isolated kerogen fraction suggest that the kerogen conversion, in coincidence with a vitrinite reflectance range of 0.55-0.60%, commenced at considerably lower temperature value ranges between 100 and 106 °C, which have produced oils during the early stage of oil generation. The kinetic models also suggest that the commercial amounts of oil can generate by kerogen conversion of up to 50% during the peak stage of oil window (0.71-0.83%) at relatively low geological temperature values in the range of 122-138 °C. Therefore, further development of the Muwaqqar oil shale successions is highly approved in the shallowly buried stratigraphic succession in the Lajjun Sub-basin, Western Central Jordan.

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